HomeMy WebLinkAboutLot Certifications - 06/30/2022CERTIFICATION OF LOT GRADING
Pursuant to Fort Collins City Code § 26-544 & City Land Use Code § 3.3.2 (e)
Date- 3une 2022
Address: 614 East Locust Street
Lot: 21________ Block:
Subdivision:________
Permit Application #: B1508996
Larimer County Parcel #: 9713235009
Larimer County Reception #:________
(on development agreement)
I, (print) Megan L. Keefe________________________; a Colorado registered professional engineer, verify that construction
of all stormwater facilities and grading is complete and hereby submit this certification.
Please answer the following questions by initialing the appropriate response. For each question initialed "No," attach an
explanation detailing how this will affect stormwater drainage for this lot and any adjacent lots.
1. Certification includes attached Stormwater-approved grading plan. (NOTE: City's
Building Department does not approve grading plans).
No Yes
2. Certification includes the attached as-built survey dated 06/15/2022 (must be within 60
days of the date the certification is submitted) accurately and truthfully depicting
elevations for:
• Top of foundation/finished floor
• Finished grade on each side of the structure
• Quarter points along each lot line (not more than 50 feet apart)
• Break points/high points
—Swalos-
- • Duim?
■ Retaining watts—
.■* Air conditioning pads'
• Window wells
• Any other appurtenance(s) within an easement
3. All elevations are within a 0.2 foot tolerance of the approved grading plan.
Not applicable. No elevations provided on approved drainage plan.
4. The top of foundation is at least 6 inches above the highest grade surrounding the
structure.
5. There is a minimum grade of 5% away from the structure within the first 5 to 10 feet
adjacent to the residence.
No Yes
No
No
Yes
Yes
No_____Yes
W-
6. All slopes meet or exceed the minimum requirement of 2% (1% is acceptable on single
family lots when the swale is draining the runoff from only two adjoining properties)
and are not steeper than 33% (3:1).
7. All flow lines of stormwater drainage swales are a minimum of 6 inches below the
elevation of ground adjacent to the structure and will direct drainage as shown on the
Stormwater-approved grading plan.
Not applicable. No site stormwater drainage swales.
8. All downspout locations and discharge directions are shown on the as-built survey.
Runoff is directed into an appropriate drainage system or lot line swale, and it is not
directed onto neighboring properties.
No_____Yes W-
No iMrYes
mlNo |\yir~ Yes
2/14/17 rage 1
Stephen Agenbroad
6/30/2022
9. A smooth transition with no vertical offset (step) in grade is provided at the lot line to all No
adjacent properties.
10. The grading of this lot does not adversely affect neighboring properties or City No
infrastructure.
11. Landscaping has been completed prior to survey, if not, please indicate who will be No
responsible for completing landscaping:__________________________________
12. Final site cleanup has been completed. No
13. I personally visited the site as part of the certification process, and in my professional No
opinion, the as-built survey is an accurate representation of the site conditions.
Yes
Yes
Yes
Yes
Yes
jyC
w
14. Based on this information, I certify that (check one):
□ The elevations and drainage patterns of the lot/site are in substantial conformance with the City
approved drainage and grading plan for the property (information attached).
^The elevations and drainage patterns of the lot/site as measured are in general conformance with the
/ City approved drainage plan with exceptions (information attached). In my professional judgment the
elevations and grading of the lot/site as constructed are functionally adequate and equivalent to the
specifically approved drainage plan, and will affect stormwater drainage on and off the lot/site in a
manner consistent with the approved drainage plan. ^ /V'TTKV&f'feD*
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PE Stamp
Sign and date
Name:
Email:
Phone:
Company:
Address:
Megan Keefe
meg@keefecivil.com
970-215-6808
Keefe Civil, Inc.
3125 Crockett Street
Fort Collins, Colorado 80526
NOTE: A complete certification must be submitted at least two weeks prior to a request for a Certificate of Occupancy
for the lot/site, including, but not limited to, drawings of the lot/site showing the approved design and as-built surveyed
elevations of all structures, drainage and grading features, written information/explanation of discrepancies, and other
information necessary to confirm the above certification to:
Email (preferred) Mailing Address Questions?
WaterUtilitiesEngfSfcgov.com Fort Collins Utilities 970-221-6700
ATTN: Water Utilities Engineering
281 North College Avenue
Fort Collins, CO 80521
/
City of
Fort Collins
2/14/17 Page 2
GRADE EXHIBIT
LOT 12 BLOCK 178 SUBDIVISION FTC
COUNTY OF LARIMER STATE OF COLORADO
ADDRESS 614 LOCUST STREET, FORT COLLINS
ALLEYWAY
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LOT 12
BLOCK 178
X = EXISTING GRADE
50.00’
LOCUST STREET
I. CHRISTOPHER A. DEPAUUS, A DULY LICENSED LAND SURVEYOR IN THE STATE OF COLORADO DO HEREBY STATE
IEREON WERE DETERMINED FROM THE RESULTS OF AN ACTUAL FIELD
^SUPERVISION ON 6/15/2022 AND THE INFORMATION SHOWN HEREON IS
WDBXMY BELIEF AND KNOWLEDGE.
THAT THE ELEVATIONS
SURVEY MADE BY MEf
TRUE AND CORRECT??
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&CHRISTOPHER A. Dl
LS 38105
DATELLAV^DRAWN BY: _RDS_______
SCALE: 1”=30’
DATE: 6/23/2022
JOB NO. 20220323
KING SURVEYORS
650 E. Garden Drive | Windsor, Colorado 80550
phone: (970) 686-5011 | fax:(970) 686-5821
www.contact@kingsurveyors.com CLIENT: DAVIDSON
KEEFE CIVIL, INC
3125 Crockett Street
Fort Collins, Colorado 80526
(970) 215-6808
meg@keefecivil.com
June 29, 2022
Fort Collins Utilities
Attn: Water Utilities Engineering
281 North College Avenue
Fort Collins, Colorado 80521
RE: 614 East Locust Street Certification of Lot Grading
To Whom it May Concern:
The elevations and drainage patterns at 614 East Locust Street, as shown on the attached
grade exhibit by King Surveyors (surveyed 06/15/22), are in general conformance with the City
of Fort Collins-approved drainage plan contained within the site’s drainage memo by Quality
Engineering (04/01/16) aside from the following exceptions outline below.
Certification Item 3: A grading plan was not approved for the site and elevations were not
provided on the approved drainage plan; therefore, site elevations have not been verified to
being within a 0.2 ft tolerance.
Certification Item 7: No stormwater drainage swales were required with site grading.
Certification Item 8: Downspout locations and discharge directions were not provided on the
as-built survey. Since all but two downspouts are piped underground and into the dry well, it
was not easily identifiable to King Surveyors where the pipes were routed onsite. When visiting
the site with the property owner, I was able to verify the following downspout locations.
In an effort to protect in place an existing tree, a very small portion of the roof on the northern
614 East Locust Street Certification of Lot Grading
Page 2 of 2 June 29, 2022
garage drains towards the alley, as shown below.
Please do not hesitate to reach out to me if you have any questions or comments regarding the
above items. It is my professional opinion the elevations and drainage patterns, as shown
below, at 614 East Locust Street are in general conformance with City of Fort Collins’ site
grading policies.
Best regards,
Megan L. Keefe, PE
Keefe Civil, Inc.
Cc: John Davison, Property Owner
Rick Shatzel, King Surveyors
f QUALITY vx ENGINEERING
March 1,2016 V\(
WWW.QUALITY-ENGINEERING.COM
Mr. Dan Mogen
City of Foit Collins Engineering Department
281 N College Avenue
Fort Collins, Colorado 80524
RE: Drainage Memo - 614 E. Locust Street
614 E. Locust Street, Fort Collins (Larimer County7), Colorado 80525
QE Project No. 6283-01
Mr. Mogen:
The purpose of this letter is to address drainage impacts to the existing 0.22 acre property located at 614
E. Locust Street due to the proposed out-buildings located in the northern portion of the property. The
site is situated in Lot 12, Block 178, City of Fort Collins, County of Larimer, State of Colorado.
Specifically, the property is located midway between Smith Street and Stover Street and bound by East
Locust Street to the south and a common alley access-way to the north. The subject property is
surrounded by residential properties to the west, east, across the alley to north, as well as across Locust
Street to the south.
The existing property currently consists of a house, sidewalks, small storage sheds, and mature
landscaping. The proposed work on the property shall consist of the construction of two small sheds at
the north end of the lot. The existing structures and improvements located at the south end of the
property are to remain unchanged. The existing site currently drains north to a local low-point at the
north edge of the property, adjacent to the existing alley.
The proposed drainage plan for the site follows historical patterns as closely as possibly, while
improving drainage and water quality issues that currently exist on the site. Existing and proposed
runoff conditions were analyzed as a single basin, due to the topography of the site.
Developed runoff from the basin will be routed north, into natural flowlines conveying the flows into a
proposed earthen depression constructed with a Dry-Well at the depression’s low point (to allow water
to enter inlet from all sides). Due to this unique, historical, city drainage basin not having an outlet, as it
is the local low-point, the proposed depression and Dry-Well cannot have an underdrain outlet.
Therefore, the Dry-Well shall be considered as a point of infiltration to mitigate developed storm water
runoff.
QUALITY ENGINEERING, LLC (970) 416-7891 2637 MIDPOINT DRIVE, SUITE E FORT COLLINS, COLORADO
Page 2
Drainage calculations are provided for this project due to the increase of impervious area on the existing
subject lot and to verify that increased flows will not adversely impact adjacent properties. Since the
existing lot does not have any adverse impact to adjacent properties, a design is proposed to increase the
site’s infiltration with the addition of the Dry-Well, in addition to detaining the difference in volume of
runoff due to the site’s increased imperviousness. This design was also chosen based on the survey and
site plan data provided to the designer being limited to only the subject property, therefore limiting
existing versus proposed drainage conditions analysis.
For a comparison of the existing and proposed sites, the existing 2-year historical flow shall be used for
a baseline for the drainage basin. The 2-year, existing flow rate is 0.78 cfs/acre for the subject property
(See calculations in Appendix). From these calculations and factors, the site produces an excess runoff
detention volume of 62 cubic feet needed storage capacity over the existing site due to the proposed
building additions.
The rear (north) yard area of the lot was selected as the location for the depression and Dry-Well to
follow existing drainage patterns as closely as possible as well as maintain as much distance as possible
to the surrounding adjacent homes. On December 10, 2015, Soilogic performed a borehole test within
the vicinity of the area of the proposed Dry-Welt to determine the existing depth of the clay soil layer.
The depth of clay on-site is approximately 14-feet deep, and therefore the proposed Dry-Well shall also
be a depth of 14-feet, to allow maximum infiltration to the sand layer beneath the clay. Because the
Dry-Well is being extended to the depth of the sand soil layer, it is anticipated that the proposed release
rate will be increased from 0.78 cfs/acre to 1.08 cfs/acre. This difference of 0.3 cfs is accounted for by
dividing said flow by the area of the manhole base (pi*RA2 = 12.56 sf), leaving 0.024 vertical feet of
drop in the manhole per second. This is also equal to 1.4 vertical feet per minute of infiltration.
It is also proposed that the Dry-Well be constructed of a typical 4-foot diameter manhole to a depth of
14-feet. The Dry-Well shall be built with 2.5-feet of (+/-)9-inch Rip Rap at the bottom of the structure.
The top 11.5-feet of the Dry-Well shall be left as pure storage volume, providing well over the required
62 additional cubic feet. The development of the lot as proposed, along with the Dry-Well feature will
enhance and improve the drainage on this site, as well as the entire block, as the back yard of this lot
appears to in the vicinity of the local low-point within the area.
The City of Fort Collins Stormwater manual amending the Urban Storm Drainage and Flood Control
District (USDFCD) has been used for drainage design guidance.
Please see the attached hydrologic basin parameters, 2-year and 100-year existing & developed flow rates.
In summary, the grading and drainage design for the proposed home addition and garage at 614 East
Locust Street complies with the requirements of Urban Storm Drainage and Flood Control District as well
as the City of Fort Collins’ Storm Drainage Criteria. The proposed changes have nearly negligible effects
on the historic drainage system of the lot. Please see the attached grading plan and drainage plan. If you
have any questions or require additional information, please call at (970) 416-7891.
Sincerely,
QUALITY ENGINEERING, LLC
Made M 0/Vuxnns
Mark Morrison, El
Project Manager
Attachments -
Appendix A
-Existing and Proposed composite ‘C’ values
-Existing and Proposed flows (cfs)
-City of Fort Collins Existing Detention Spreadsheet
-City of Fort Collins Proposed Detention Spreadsheet
-Drainage Plan
Reviewed by,
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u CEMody G
Principal Engineer
Robinson Engineering, Inc (970) 217-4960
319 South Grant Avenue, Fort Collins, Colorado 80521 PO Box 2459, Fort Collins, Colorado 80522
19 January 2022
Building Services
City of Fort Collins
28 i N College
Fort Collins, CO 80524
and
John Davison
214 Locust Street
Fort Collins, CO 80525
Dears Sirs,
RE: DrvWell Inspection, Davison Residence, 614 Locust Street, Fort Collins, CO 80524. REI
Project 15-031.
There was a need to install a dry well on the property during the construction of the garage and workshop
structures. Our office originally looked at the drywell design, but it was somewhat outside of our normal
practice of work. The dry well design was done by a Cody A. Geisendorfer, Colo PE 41326, functioning
as Quality Engineering, 11c. Reportedly, Mr Geisendorfer is no longer responding to local customers. I
was not able to contact him. While I did propose a dry well design, our design was not the one submitted
to the building department. We did not design the dry well. The calculations to size the cistern were not
done by our office. Because of our work designing the two adjacent buildings, this inspection is a
professional courtesy inspection.
I have reviewed the 1 March letter from Quality Engineering Inc to the city, as well as the plot plan
showing the well location and a cross section of the dry well. I have been on site plus reviewed photos
supplied by Mr. Davison.
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Project: 15-031
According to my observations, I concur that the dry well is 14’ deep and 4’ diameter with 2.5’ (min) of
rip rap or crushed rock at the bottom. The dry well is concrete conduit with a concrete cap and integral
drain grate. Based on the information supplied to our office, the dry well conforms to the specifications
provided to Mr. Davison.
Sincerely,
Geoff Robinson, PE
Civil/Structural Engineer
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The inspection and comments are limited to the specific items listed in this letter and in no way imply a certification or complete inspection of
the structure, its systems or site work. We have no control over workmanship, contractor decisions or site events. No liability is assumed for
future loss of value, marketability or any other loss claims.
Project: 15-031 19 January 2022